Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, generator, gearbox, nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of wind using known foil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
The size, shape, and weight of rotor blades are factors that contribute to energy efficiencies of wind turbines. An increase in rotor blade size increases the energy production of a wind turbine, while a decrease in weight also furthers the efficiency of a wind turbine. Presently, large commercial wind turbines in existence and in development are capable of generating from about 1.5 to about 12.5 megawatts of power. These larger wind turbines may have rotor blade assemblies larger than 90 meters in diameter. Accordingly, efforts to increase rotor blade size, decrease rotor blade weight, and increase rotor blade strength, while also improving rotor blade aerodynamics, aid in the continuing growth of wind turbine technology and the adoption of wind energy as an alternative energy source.
As the size of wind turbines increase, particularly the size of rotor blades, so do the respective costs of manufacturing, transporting, and assembling the wind turbines. The economic benefits of increased wind turbine sizes must be weighed against these factors. For example, the costs of pre-forming, transporting, and erecting a wind turbine having rotor blades in the range of 90 meters may significantly impact the economic advantage of the larger wind turbine.
For example, the costs of transporting rotor blades increase as the size of the rotor blades increase. One known method for transporting rotor blades involves the use of large trucks, such as tractor-trailers. The rotor blades are loaded onto trailers, which are hauled by the trucks to a desired destination. Frequently, however, this transportation method is hindered by the existence of height-restricting obstacles, such as bridges, that exist along various routes for hauling the rotor blades to a desired destination. For example, large, curved rotor blades with flapwise or edgewise bending may have clearance heights that are higher than the heights of the height-restricting obstacles, thus inhibiting the rotor blades from passing under the height-restricting obstacles.
One known solution to the problem of transporting a rotor blade under height-restricting obstacles involves turning the rotor blade sideways, such that the rotor blade is width-restricting rather than height-restricting, when the truck passes under a height-restricting obstacle. This solution, however, is expensive and time-consuming, requiring, for example, that oncoming traffic passing under the height-restricting obstacle be halted while the truck is passing through. An alternative solution involves loading the rotor blades into, for example, boats or barges, rather than trucks, and transporting the rotor blades along waterways to a desired destination. This solution, however, is also expensive and time-consuming, and frequently the desired destination of a rotor blade does not have waterways leading to it. A further alternative solution involves separating the rotor blades into smaller separate rotor blade components for transport. However, separating a rotor blade may weaken the fibers and/or other reinforcing structures within the rotor blade, thus undesirably weakening the rotor blade.
Accordingly, there is a need for a transportation system and method that allows for rotor blades and other large turbine components to pass under height-restricting obstacles. Further, a transportation system and method for rotor blades and other large turbine components that are relatively efficient, fast, and cost-effective would be desired.